Spring construction



Jan. 6, 1959 H. c. FLINT SPRING CONSTRUCTION Filed July 15, 1950 IINVENTOR.

flgZd/Ya/ [fr/2772? SPRING CONSTRUCTION Hyland C. Flint, Birmingham,Mich., assignor to American Metal Products Company, Detroit, Mach, acorporafion of Michigan Application July 15, 1950, Serial No. 174,111

8 Claims. (Cl. 155-179) This invention relates to spring constructionsand, in particular, to those embodying sinuous or zigzag springs of theprearched type as disclosed and claimed in Kaden Reissue Patent No.21,263. Features disclosed in this application are related to thosedisclosed in the inventors copending application No. 152,727, filedMarch 29, 1950, entitled Spring Supporting Strips Having A Top SeatingPortion Spaced Above A Bottom Reinforcing Portion, now Patent No.2,629,431, and assigned to the assignee of the present invention.

In the preferred practice of the present invention, as well as in theinvention of the aforementioned copending application, the zigzag springunit comprises at least two vertically spaced web portions, the upper ofwhich defines the resilient load supporting or seating surface. Thevertically spaced web portions are each longitudinal and lie in theplanes of projection of each other, and one or both of the webs aremounted upon and secured to the rails which extend transversely of thewebs, and which are located at the front and rear of the seat. One orboth of the zigzag springs which provide the web portions have ends thatare bent transversely to the web and which serve to space the upper webabove the lower. Relative longitudinal movement of these end portionswhich space the upper and lower webs is yieldably resisted by the lowerweb which is fixedly secured thereto. Thus, a closed loop or ring ofzigzag spring wire is pro vided and its ability to resiliently supportloads enables lighter springs to be used in various applications.Furthermore, this type of construction is relatively easy to manufactureand also may be readily adapted to provide various desired contours anddepths of spring construction. As illustrated in the aforementionedapplication, it is also possible to secure the lower web to the rearrail and allow the end of the upper web to deflect relative to this railthus providing adequate toe room or space beneath the seat as well asresilience and comfort at the rear of the seat. Room beneath an edge ofthe cushion may also be provided by allowing the webs to overhang therails.

With reference to the multi-web zigzag spring unit, it is an object ofthe present invention to provide increased resistance to deflection ofthe upper web at a selected point or points thereon. This isaccomplished by means of a sinuous strip that interconnects anintermediate point onthe upper web with the lower web, this strip beingpreferably formed on either of the zigzag springs or, if desired, may bea separate element.

Other objects are to provide foot room beneath the front of a seatconstructed from sinuous spring units and to improve the appearance ofthe spring cushion construction which is obtained when upholstery andpadding are applied to the spring units. These are accomplished byforming the front of the seat so that the spring units overhang the railand by the use of both upper and lower border wires at the front of thespring units.

Other objects and features of the invention will appear Patented Jan. 6,1959 upon consideration of the accompanying drawings, wherein:

Figure 1 is a plan view with parts of the upholstery broken away toreveal the spring strips of a seat construction embodying the invention;

Fig. 2 is a section taken along the line 2--2 of Fig. 1 showing thezigzag unit of this invention in side elevation;

Fig. 3 is a perspective view of a clip that may be used to interconnectthe zigzag springs which provide the upper and lower web' portions; and

Fig. 4 is a section along a line corresponding to line 2-2 of Fig. 1 butthrough a'modified form of spring unit. 7

The invention as shown in the drawings is applied to the seatconstruction 1, although it will be evident to those in the art that itcan be used in spring constructions employed for other purposes. Theseat 1 has a tubular frame 3 which includes a front rail 5 and a rearrail 7 that is spaced above the front rail so as to provide toe room atthe'rear of the seat 1. The zigzag spring units 9 are mounted upon thefront and rear rails 5 and 7 and are parallel to each other and spacedtransversely of each other along the frame 3. Preferably, each of thespring units that is used to make up the spring construction is the sameexcept perhaps for the endmost spring units which must often be adaptedto serve in cramped areas.

The zigzag unit 9 consists of a sinuous spring 11 that provides theupper web 13 and a sinuous spring 15 which provides-at least part of thelower web 17. As is well known, the sinuous spring strips 11 and 15consist of spring wire that is bent in a zigzag fashion so as to formadjacent loops that open in opposite directions, and, as

indicated above, are preferably prearched in accordance with theteachings of the Kaden Reissue Patent No. 21,263. thereof which is bentbeneath the front of the web 13 to form a substantially upright leg 19and also a portion extending from the bottom of the leg 19 which is bentat an angle thereto and extends rearwardly and downwardly to terminatein a loop 23 that may be bent up wardly' at an 'angle to the portion 21.The rear end. of the spring 11 has a portion 25 bent forwardly beneaththe rear end of the web 13 and a portion 27, separated from portion 25by a loop 29, that extends upwardly and forwardly and is pivotallyconnected bv a clip 31 to the web 13 at a point sli htly forward of themidpoint of the web. Spring 15, which provides the lower web 17, isnon-pivotally secured at its extreme forward loop.33 by a clip 35 to theloop 23 of the spring strip 11. An intermediate loop 37 of the spring 15is connected bya clip 35 to the loop 23' of the spring strip 11. It willbe evident that the webs 13 and 17 together with spring portions 25, 19,and 21 form' a closed resilient loop or ring, all parts of which serveto resiliently support loads. The resistance of the upper'web 13 iscontrolled or varied by the spring section 27, the effect being toprovide a somewhat softer seating surface to the rear of the clip 31than forward thereof. Q

The spring 15 is mounted upon and secured to the rails 5 and 7. Ifnon-pivotal connection is desired, and this is preferred at present, themounting may be conveniently accomplished through the medium of clipsformed on the rails in accordance with the teachings of the presentinventors copending application, Serial No. 88,293, filed April 19,1949, entitled Spring Supporting Clip Having A Locking Tongue, assignedto the assignee of the present inventionf-now Patent No. 2,695,658,granted November 30, 1954. A loop 39 of the web 17 that is slightly tothe rear of the loop 33 is inserted in the -clip41 that is provided onthe rail 5 whereby the spnng'15 is non-pivotally secured to the rail.The rear 'The spring 11 has a portion at the front end end of the spring15 is bent upwardly in a section 43 that is transverse to the web 17 andthe upper end of section 43 is inserted in and secured to a clip 41formed on the rea r ra'il 7. This arrangement provides for toe roombeneath the rail 7 and also allows the rear end of web 13 to deflectdownwardly'in'side of and beneath the surface of rear rail '7. If thefront rail is elevated above the floor of the auto, room will beprovided beneath the front of the seat because of the overhang of thesubstantially trapezoidal shape of the' forward section of the springunit, that is, the section forward of and including spring section 27.

The modified formQof spring unit 51 that is shown in i Fig. 4 is thesame in principle as the spring unit 9, the' main difference being thatthe support for the upper web is provided by a portion bent from thelower spring and the unit is connected to the front rail 5 by a portionbent from the upper spring. In this construction, the upper web 53 isprovided by the sinuous spring'55. The front of the spring 55is bentdownwardly to form a substantially upright leg 57 which corresponds tothe leg 19, and is then bentat an angle to the leg 57 to provide adownwardly and'rearwardly extending section 59 which may be slightlyconcave upwardly as indicated. The section 59 has a loop 61 that issecured by a clip 41 to the front'rai-l 5. The rear end of the upperspring 55 is bent downwardly and inwardly beneath the spring in asection 63 which may terminate in a loop 65 that is bent forwardly andupwardly at a slight angle to the direction of the section 63. The lowerspring '67 provides a lower. web 69 which, however, in this case, is notthe complete lower web for the zigzag unit 51, this being providedby thesections 59 and 69 acting together for which purpose they arenon-pivotally interconnected 1 in their respective loops "71 and 73 by'aclip 35. The spring 67- has a portion 75 that is bent forwardly andupwardly from the loop 73 and which is connected at its upper end by asuitable clip 77 to a point on the upper web 53. As in the case of thezigzag unit 9, the lower spring 67 has a section 79 that is bentupwardly from the web 69 to be secured by clip 41 to the rear rail 7. Inthe spring unit 51, the upper web 53, the lower webs 69 and 59, and thefront and rear portions 57 and 63 p of the spring 55 provide a closedloop. Auxiliary support for the upper web is provided by the section 75which'interconnects the upper and lower webs and which is formed fromthe spring 67. It is clear that the rear of the web 53 can deflectinside rail 7 so that a soft rear edge is obtained in combination withtoe room and that the forwardend overhangs the rail 5.

. In accordance with the invention, upper and lower border wires '81 and83, respectively, are secured to the spring units 9 and 51 by' suitableclips 85. As is well known, the border wires 81 and 83 extendtransversely of the seat and are connected to each of the plurality ofspring units 9 or 5-1; The upper borderiwire 81 is connected to theunits at the juncture of the upper web and the front legs 19 or 57 whilethe lower border wire 83 is connected'to the spring units at the apex.

of the angle between the sections 19 and 21, or 57 and 59. A layer 87 ofburlap or other fabric is wrapped around the exposed surfaces ofthespring units, it being shown as extending from the front rail 5around the border wires 83 that is 'rearwardly over the rear rail]? tobe connected by suitable hog rings or the like tofthe lower spring or 67at'the base of the upright sections 43 and 79. Suitable padding orstuffing 89 is placed over the fabric 87 and this is held in position bythe outermost layer of upholstery cloth 91 which is also connected bysuitable clips or the like to front and rear portions of the springconstruction. The use of 'the substantially upright legs19 and 57, inconjunction with upper and lower border wires that are directlyconnected thereto, provides a desirable appearance for the front of theseats "and eliminates the necessity for spacers of one type or sheetmetal which has a preferably flat web 92 and' upright or transverseflanges 93 at the opposite longitudinal edges of web 92, which may betapered toward each other if the spring loops are so formed, thetransverse sides of the clip being open. The height of the flanges 93and their transverse spacing is such that they may snugly receive twosuperposed loops of the springs and thereafter be bent inwardly over thetop of each leg of the loop whereby the loops may be tightly clampedtogether.

It will be evident to those in the art that the structure herein shownis subject to modification within the spirit of the several features ofthe invention. For example, the benefits of space beneath the front endof the seat that accrue from the use of the overhang may be obtainedwithout the use of a lower web, though it is preferred at present, thatthe web be used.

What is claimed is: v

l. A zigzag spring unit comprising a closed loop of sinuous spring wireincluding an upper web and a lower web, a sinuous spring strip inside ofsaid loop interconnecting an intermediate point on the upper web withthe lower web, and a sinuous spring portion extending longitudinallyfrom the lower web and then bent upwardly toward the upper web wherebyit is adapted for connection to a rail of a-supporting frame in a mannerto permit the upper web to deflect downwardly in front of the rear rail.g

2. A zigzag spring unit comprising a closed loop of sinuous spring wireincluding'an upper web and a lower web, a sinuous spring strip inside ofsaid loop interconnecting an intermediate point on the upper web withthe lower web, and a sinuous spring portion extending longitudinallyfrom the lower web beyond the end of the upper web and then bentupwardly toward the upper web whereby it is adapted for connection to arail of a supporting frame whereby the upper web may deflect downwardlyin front of the rear rail.

3. A zigzag spring unit comprising a first sinuous spring strip having aweb portion, the front end of said strip being bent transversely toextend beneath the web, the rear end of said strip being bent to extendbeneath the'web and then up to and connected to an intermediate partofthe web, and a second sinuous spring strip having a web portionbeneath the first strip web and a front portion 'nonpivotally connectedto the front endof the first strip, said second strip being nonpivotallyconnected to the rear end of the first mentioned strip at a point spacedbeneath the upper web.

7 4. A zigzag spring unit comprising afirst sinuous spring strip having.a web and front and rear ends bent to e);-

tend beneath the web, a second sinuous spring having .a.

web beneath the web of thelfirststrip, said second strip beingnonpivotally connected to the front and rear ends of said first springand having a portion extending .upwardly from its web and connected toan intermediate point on the upper web. i

5. In a spring construction, the combination of a frame having front andrear rails parallel :to each other, transversely spaced spring unitsspanning the space between said rails, said units each comprising spacedupper and lower webs and sinuous spring elements securing the front andrear ends and an intermediate portion of the upper web to the lower web,said lower web of each unit being nonpivotally secured to the front andrear rails, said lower web being located below the rear rail andextending beyond the rear end of the upper web whereby said upper webcan deflect inside of the rear rail.

6. In a spring construction, the combination of a frame having front andrear rails parallel to each other, a plurality of spaced parallelsinuous spring .units spanning the space between said front and rearrails, said units each including a first sinuous spring strip having afirst web and front and rear portions bent to extend beneath the web,the webs of the first strips of said units each providing a resilientsurface, said units including a second sinuous strip beneath the firstsecured to the front and rear portions to provide a second web beneaththe first, a sinuous spring element integral with one of said stripsinterconnecting an intermediate point on the first web with said secondweb, and means securing the units to the front and rear rails, the frontportions of said units substantially overhanging the front rail andbeing of substantially the shape of a trapezoid.

7. The invention set forth in claim 6 wherein said second web of eachunit is located below the rear rail and extends beyond the rear end ofthe first web and is connected at its end to said rail whereby saidfirst web can deflect inside of said rear rail.

8. In a spring construction having a frame with a front rail, a sinuousspring strip including a load supporting web and a front end portionbent to extend beneath the web, said strip extending transversely tosaid rail and the front portion and web thereof substantiallyoverhanging the front rail to provide a cantilever section of said stripextending forwardly of the front rail, said front end portion comprisinga section of said strip bent at. substantially right angles to the weband extending a substantial distance below the web and then bentrearwardly toward the front rail and substantially parallel to the web,and means for securing the rear end of the strip to the frame.

References Cited in the file of this patent UNITED STATES PATENTS1,302,119 Young Apr. 29, 1919 2,122,979 Gleason July 5, 1938 1 2,251,043Freeman July 29, 1941 2,251,049 Haberstump July 29, 1941 2,330,906 NeelyOct. 5, 1943 2,526,184 Williams et a1 Oct. 17, 1950 2,526,250 MatthaeiOct. 17, 1950 2,591,185 Neely Apr. 1, 1952 Flint Feb. 24. 1953

